As instructed by poiuy in the above url, I made a bootable cf from app.image released by iRex. But it won't work if I use "dd" to copy root partition to cf (dd if=/dev/tffsa1 of=/dev/hda1). Besides, the size of cf will be converted to 76mb after dd. Anyway, I have a bootable cf now.

Added:
After creating a bootable cf from app.image, I copied some dirs from root partition to cf. Now I have a bootable cf with updated firmware and my own settings. It's a perfect testbed for experiement.

Added 2:
With this cf, I can manipulate iLiad root partition with my desktop. It will be much convenient.